let fs=require("fs");
let promise=new Promise((resolve,reject)=>{
    /* promise 承诺 resolve 成功 reject 失败  */
    fs.readFile("111.txt",(err,data)=>{
        if (err){
            reject(err);
        }else {
            resolve(data);
        }
    })
});
async function asynDemo() {
try{
    let data=await Promise;
    console.log(data.toString())
}catch (e) {
    console.log(e)
}
}
asynDemo()
